Homework 1 IDL code demo

cdf2idl, 'COARE_soundings_goodset.nc'
@COARE_soundings_goodset.idl
 
qv = RH/100.*mixrat(T,p)
Tvabs = (T+273.2)*(1+0.61*qv)
Tv = Tvabs - 273.2
dz = (287.*Tvabs/9.8/p)*5 ;;; dp = 5mb
z = total(dz, 2, /cum)
 
s = entropy(T,p,qv)     ;;; test
sdry = entropy(T,p,qv*1e-5)
ssat = entropy(T,p,mixrat(T,p))
 
;;;; Plot a few
plot, s(0,*), z(0,*)/1000., ytit='z (km)', xtit='dry, actual, and saturation entropy', xra=[100,300], tit='10 sondes'
oplot, sdry(0,*), z(0,*)/1000., lines=1
oplot, ssat(0,*), z(0,*)/1000., lines=2
 
for isond = 0,10 do $
oplot, s(isond,*), z(isond,*)/1000., color=5+isond*250/10
for isond = 0,10 do $
oplot, sdry(isond,*), z(isond,*)/1000., lines=1, color=5+isond*250/10
for isond = 0,10 do $
oplot, ssat(isond,*), z(isond,*)/1000., lines=2, color=5+isond*250/10
 
;;; Pick one sounding, call it "env" e
Te = T(0,*)
qe = qv(0,*)
pe = p(0,*)
se = s(0,*)
 
;;; No, use the mean s and q
Te = total(T,1)/1726.
qe = total(qv,1)/1726.
se = total(s,1)/1726.
 
;;;; Lift surface parcel, conserving entropy and total water
invert_s, se(0),pe,qe(0), Tp,qvp
 
Tvp = (Tp+273.2)*(1+0.61*qvp) - 273.2
Tve = (Te+273.2)*(1+0.61*qe) - 273.2
 
;;; The density temperature includes condensate loading
Trhop = (Tp+273.2) *(1+qvp/0.622)/(1+qe(0)) -273.2
 
plot, Tp-Te, -pe, tit='lifted parcel Tp-Te, Tvp-Tve, and Trhop-Tve', ytit='-p (mb)', xtit='K', xra=[-2,5]
oplot, Tvp-Tve, -pe, lines=1
oplot, Trhop-Tve, -pe, lines=2
ver,0
 
plot, 9.8*(Tp-Te)/Tvabs(0,*), z(0,*)/1000, tit='Buoyancy', ytit='z (km)', xtit='m s!U-2!N or J/kg', xra=[-0.2, 0.2]
oplot, 9.8*(Tvp-Tve)/Tvabs(0,*), z(0,*)/1000, lines=1
oplot, 9.8*(Trhop-Tve)/Tvabs(0,*), z(0,*)/1000, lines=2
ver,0
 
;;; Downdraft: plenty of water, conserve entropy
;invert_s, se(40),pe(0:40),qe(40), Tdownp,qdownp
;plot, Tdownp-Te, -pe(0:40), tit='rainy downdraft parcel Tp-Te'
 
;;; Lifted Index
Te500 = T(*,100) ;;; 500mb
invert_s, s(*,0),500.,qv(*,0), Tp500,qvp500
 
LI = Te500-Tp500
thetae = theta_e(T,p,q)
 
 
;;;;; SST CHANGE TYPE THINKING +1K
qv1 = RH/100.*mixrat(T+1,p)
s1 = entropy(T+1,p,qv1)
 
invert_s, s1(0,0),pe,qv1(0,0), Tp1,qvp1
 
plot, tp1-tp, z(0,*)/1000, tit='parcel T change: initial T+1K, RH=const', ytit='z (km)', xtit='Tp over warmer SST', $
yra=[0,13]\
 
;;; CAPE
b = 9.8*(Tp-Te)/Tvabs(0,*)
dzz = dz(0,*)
hlp, total((b>0)*dzz)
 
;;; CAPE +1K
b = 9.8*(Tp1-Te)/Tvabs(0,*)
hlp, total((b>0)*dzz)
 
 
;;;;;;;;;;; entraining plume buoyancy, mean sounding
sde = entropy(Te,pe,qe*1e-5)
ssate = entropy(Te,pe,mixrat(Te,pe))
 
;;;; Plot tripod
plot, se, z(0,*)/1000., ytit='z (km)', xtit='dry, actual, and saturation entropy', $
xra=[100,300], tit='mean sounding'
oplot, sde, z(0,*)/1000., lines=1
oplot, ssate, z(0,*)/1000., lines=2
 
;;;; Now entrain
eps = 1./100 ;;; fractional entrainment rate per mb
M0 = 1. ;;; unit mass flux at cloud base
dp = 5 ;; mb
 
;;; Entrainment mixes q and s
M = M0 * exp((1005-pe)*eps)
Mq = (M0*qe[0]) + cumulate(eps*dp *M*qe)
Ms = (M0*se[0]) + cumulate(eps*dp *M*se)
 
qplume = Mq/M
splume = Ms/M
 
!p.multi=[0,2,1]
plot, qe, z(0,*)/1000., tit='q of environment and plume'
oplot, qplume, z(0,*)/1000., color=250
 
plot, se, z(0,*)/1000., ytit='z (km)', xtit='dry, actual, and saturation entropy', $
xra=[100,300], tit='mean sounding'
oplot, sde, z(0,*)/1000., lines=1
oplot, ssate, z(0,*)/1000., lines=2
oplot, splume, z(0,*)/1000., color=250